Emission rates of species-specific volatiles vary across communities of Clarkia species: evidence for multi-modal character displacement
Eisen, Katherine; Geber, Monica; Raguso, Robert (2021), Emission rates of species-specific volatiles vary across communities of Clarkia species: evidence for multi-modal character displacement, Dryad, Dataset, https://doi.org/10.5061/dryad.3tx95x6fx
A current frontier of character displacement research is to determine if displacement occurs via multiple phenotypic pathways and varies across communities with different species compositions. Here, we conducted the first test for context-dependent character displacement in multi-modal floral signals by analyzing variation in floral scent in a system that exhibits character displacement in flower size, and that has multiple types of sympatric communities. In a greenhouse common garden experiment, we measured quantitative variation in volatile emission rates of the progeny of two species of Clarkia from replicated parental communities that contain one, two, or four Clarkia species. The first two axes of a constrained correspondence analysis, which explained 24 percent of the total variation in floral scent, separated the species and community types, respectively. Of the 23 compounds that were significantly correlated with these axes, nine showed patterns consistent with character displacement. Two compounds produced primarily by C. unguiculata and two compounds produced primarily by C. cylindrica were emitted in higher amounts in sympatry. Character displacement in some volatiles varied across sympatric parental communities and occurred in parallel with displacement in flower size, demonstrating that this evolutionary process can be context-dependent and may occur through multiple pathways.
All procedures for data collection and processing are listed in the manuscript. All scripts used to analyze the data are available on GitHub (https://github.com/kate-eisen/clarkia-scent/) and Zenodo (https://doi.org/10.5281/zenodo.4623613).
File_structure.txt describes which files relate to which analyses. Column_descriptions.csv contains the units and any notes relevant to each column in each data file.
National Science Foundation, Award: DGE-1650441
National Science Foundation, Award: DEB-1754299
National Science Foundation, Award: DEB-1342792